Method of preventing condensation on a surface housing an electronic apparatus

Abstract

Moisture condensed on a circuit board can cause dendritic growth which can short out a circuit. Such sensitive areas are protected from condensation by filling cavities in an assembly with insulating material to exclude moisture bearing air. Foamed plastic is molded or stamped into shapes which conform to a cavity and are inserted into the assembly. The plastic body is held against the circuit board to preclude condensation on the board. Adhesives and sealants are not required.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A method of precluding condensation on a surface adjacent a cavity in an electronic apparatus comprising the steps of: forming an insulating body to the shape of the cavity; then   preventing condensation on the surface by inserting the body into the cavity adjacent the surface to thereby displace air from the cavity, to thereby preclude condensation; and   enclosing the apparatus and the insulating body in a housing.   
     
     
       2. The invention as defined in claim 1 wherein the electronic apparatus includes a circuit board having a moisture sensitive surface and wherein: the body is placed against the circuit board to inhibit moisture condensation on the moisture sensitive surface.   
     
     
       3. The invention as defined in claim 1 wherein the forming step comprises: stamping the body from an insulating sheet of uniform thickness.   
     
     
       4. The invention as defined in claim 1 wherein the forming step comprises: molding the body in a mold shaped substantially like the cavity.   
     
     
       5. The invention as defined in claim 1 wherein the insulating body comprises a foamed polymer. 
     
     
       6. The invention as defined in claim 1 wherein the insulating body comprises expanded polypropylene.